Origins of the Roman Candle, Sparkler, and Gunpowder
Although the discovery of fireworks can’t be pinned down to an exact dynasty, most credit the Chinese with the happenstance invention of gunpowder around 2000 years ago.
The creation and origins of gunpowder are really what lit off the fireworks story, and as the story goes, apparently a common cook accidentally mixed three common kitchen ingredients (KNO3 – Potassium-Nitrate, Sulfur, and Charcoal) thereby producing a volatile mixture that would soon come to be used in Chinese warfare.
Among other applications, were the creation of exploding bamboo sticks and a sort of rat missile, in which a live rat, propelled by explosives, would be aimed at enemies on horseback in one of the earliest and most bizarre examples of psychological warfare in history.
History of Fireworks
Black powder is the largest component of fireworks. It was the first chemical explosive discovered by man in China approximately 2000 years ago. In the 10th century, China black powder was used by monk Li Tian to create the first firework, a firecracker. The bamboo shoots filled with black powder were set off at the new year to scare away evil spirits, a practice still used in China today.
It is widely acknowledged that black powder was introduced to Europe by Marco Polo in the 13th century. Although at first it was predominately used for military purposes, there was some use for fireworks.
By the 15th century, the popularity of fireworks had spread across Europe. In France, in 1560 the first firework display was used to mark the ascension to the throne of Francis II. Fireworks were also popular in England and mentioned in at least one of Shakespeare’s plays.
During the Renaissance, there were two European schools of pyrotechnics, The Italian school concentrated of firework effects and in the 1830s they discovered how to add color. The German school concentrated on scientific advancement.
Fireworks have also become a big part of the celebrations of Independence Day in the USA after 1777 when they were first used.
Marco Polo and Fireworks Beginnings
But before gunpowder could be transformed into fireworks, it had to be rescued from the Orient and brought to the modern world, which Marco Polo did sometime during the 13th Century, although some accounts credit the knights of the Crusades with unleashing the “fire-chemical” (huo yao) from Far East.
Whatever the case, by 1560 European scientists had further refined the volatility of the mixture by using the following ratios: 75% saltpeter, 15% Charcoal, and 10% Sulphur. That was more or less the bang behind fireworks and still is today, but credit is given to the Italians and sometimes Germans for using aerial shells and various slow-burning compounds to create brilliant erupting fountains of color.
The whole of Europe was fascinated and quickly became transfixed on the idea of controlled fire, especially the wealthy, for whom grand fireworks displays became interwoven with societal standing. Such displays became so popular, in fact, that Queen Elizabeth created the position of “Fire Master of England.” (She also, incidentally, had her own personal brewmaster.)
King James II was also so pleased with the fireworks display that during his coronation he knighted his Fire Master. Even Shakespeare notes that “certain stars shot madly from their spheres” in A Midsummer Night’s Dream. So enamored with the concept of controlled fire was Europe at this time that yellows and oranges (from steel and charcoal) would be enough variety in color for another 200 plus years.
Modern Science & Chemistry of Fireworks
A rainbow of colors would not be added to fireworks until around the 1830s when Italian chemists started adding trace amounts of metals and salts that burned at high temperatures. These salts created beautiful and exciting new colors, and other additives produced interesting effects, like calcium to deepen colors, titanium to make sparks, and zinc to create mysterious smoke clouds.
Chemists also found that strontium created red fireworks, barium created green, copper made blue, sodium made yellow, and white/gold came from aluminum and magnesium. As the art of fireworks matured, the anatomy changed as well, with a standard makeup (according to PBS Nova on-line) that consists of a launch tube (the main container with a charge of gunpowder in the bottom), main fuse, lift charge (the main source of propulsion), stars (marble-size units containing metal salts and color-producing chemicals), breaks (cardboard sections each containing gunpowder), and spegettes (small time-release fuses loaded in the breaks used to ignite to stars).
Fireworks consist of a container, usually cardboard or plasterboard filled with pyrotechnic stars. Generally, a star contains fuel, oxidizing agents, reducing agents, regulators, coloring agents, and binders plus fuse.
- fuel – usually charcoal-based black powder
- oxidizing agents – produces oxygen required to burn the mixture
- reducing agent – burns the oxygen-producing hot gas
- regulators – metals added to control or change the speed of reaction
- binders – a paste-like substance which holds the mixture together, usually a type of starch called dextrin
- coloring agents – metals or salts added that produce a color: strontium (red), copper (blue), barium (green), sodium (yellow/orange), calcium (orange), iron (gold). Mixtures can be used to produce other colors for example strontium and copper will produce purple.
Fireworks Fact and Stats
This new science and technology produced a brighter, more vibrant, more colorful, and longer-lasting display of color and light. Speaking of light, it travels almost 170 times faster than sound (as any high school science book will tell you).
This is why fireworks seem to have a duel impact – first lighting up the sky (caused by burning chemical salts), then, moments later, a booming sound, which is caused by the rapidly expanding gas (produced by igniting the chemicals) bursting through the shell and displacing the air around it very quickly.
Sound travel at 768 mph, or about one mile in five seconds. According to Robert Krampf’s Science Education Co. on-line, this movement of air creates reverberating waves, which the ear perceives as sound.
Different Types of Firework
Today fireworks come in many different shapes and sizes, but they are based on a few different types.
- Firecrackers – A small cylinder of a paper envelope filled with black powder with a short fuse, producing a small explosion.
- Rockets – The basic form is a cylinder filled with black powder. When the lit fuse reaches the black powder it is ignited. Due to the shape and construction of the rocket, the expanding volume of hot gas produced is forced out of the bottom resulting in a thrust force pushing the rocket upwards. A second internal fuse (timer fuse) ignites the bursting charge, which breaks open the rocket igniting the stars.
- Fountains – A cardboard tube mounted vertically on a plastic base. The fuse enters at the top of the fountain through a clay plug called a “choke”. The choke prevents all the hot gas from venting after ignition producing a weak spray. Once the fuel is ignited the gas builds up. This means when the gas and stars escape out of the choke it reaches a faster speed and a higher stream. The fountain can be layered to produce different effects.
- Roman Candles – This had a similar construction to the fountain, but it is the internal layering that is different. The layers start with a delay charge, followed by a layer of stars then a lifting charge, these layers are then repeated. The delay charge is tightly packed fuel, which controls the burn and prevents the ignition from reaching the lifting charge before the stars are ignited. The layer of stars is packed loosely so that the lifting charge is ignited at the same time. The lifting charge pushes the stars out the top of the firework as well as igniting the next layer of delay charge.
- Mine – This is a ground-based shell. The lifting charge is at the bottom of the tube where the fuse enters. Once ignited the stars are propelled out of the top of the tube in a “V” shaped pattern.
- Aerial Shell – A complex firework consisting of two parts. A mortar tube ensures that the shell launches in the correct direction. Inside the mortar, tube is the shell that is cased in a container. The fuse ignites a lifting charge launching the shell from the mortar tube and ignites a timing fuse. The timing fuse is designed to set off the bursting charge and the stars when the shell reaches the top, of its trajectory.
- Cake – A series of areal shells and mortar tubes clustered together. The mortar tubes are connected by a series of fuses. When the fuse ignites the first shell it also lights a fuse connected to the next mortar.
- Wheels – Consists of a frame attached to a post by a nail through the center. Small rockets are attached to the frame and joined by the fuses. The fuse sets off each rocket. The rocket tubes have a choke at one end producing a lot of thrusts propelling the frame around very fast.
- Sparklers – A thin wire covered with a metallic pyrotechnic compound at one end. The compound burns slowly giving off a large number of bright sparks.
The Largest Cathrine Wheel was 25.95m in diameter and was set off by the Newick Bonfire Society Ltd on 30th October 1999 in Newick, England.
Largest Firework Display consisted of 66326 fireworks and was organized by Maceob’s Pirotecnia Lda on 31st December 2006 in Funchal, Madeira, Portugal.
The Longest Firework Waterfall called “Niagara Falls” was 3125.79m high and took place on 24th August 2003 at the Ariake Seas Firework Festival in Fukuoka, Japan.
The largest number of firework rockets launched in 30 seconds was 56405 and was organized by Dr Roy Lowry on 16th August at the 10th British Firework Championship in Plymouth, England.